This invention relates to electrical connective means for effecting the external connection to an electron tube and more particularly to improved external electrical connective means for a multi-element electron tube having an isolated conductive lead extending from the closure portion thereof.
Many types of electron tubes, as for example, cathode ray tubes of the kind utilized in television and allied display applications, normally utilize a type of envelope closure having therein a protruding sealed exhaust tubulation surrounded by an array of substantially rigid supportive and connective leads or pins which traverse the closure and project exteriorly therefrom. Such closure constructions are usually capped by a suitable base member conventionally formed of plastic insulative material fabricated in a manner to provide a protective enclosure for the sealed tubulation, such being spatially surrounded by an array of perforations dimensioned to accommodate protrusion of the respective connective pins therethrough. Such construction effects protection for the sealed tubulation and the glass seals of the connective pins and provides strength to the protruding connective pins during insertion and removal from a compatible electrical socket means. Additionally, the base member usually incorporates a longitudinal alignment provision on the exterior of the tubulation-protection-portion to facilitate proper insertion of the respective pins into the recessed contacts of the matching tube socket. In those instances when a high voltage is directed from the electron gun assembly through one of the connective pins in the closure portion, arcing conditions sometimes develop due to the closeness of the pins in the connective array. Since arcing within the electron gun assembly, or between pins in the closure portion of the tube, may have catastrophic effects on components in the external circuitry, much effort has been directed to minimize the possibility of arching. Special efforts have been expended to insulate elements and connections within the electron gun structure in order to prevent the development of arcing conditions between adjacent elements of the tube. In addition, special insulative constructions have been incorporated into the base and socket members to minimize the possibility of arcing conditions, but in many instances, the resultant protective features produce results that are less than desired.
A successful approach to minimize arcing has been the development of a tube closure portion wherein a high voltage lead from the electron gun assembly is spatially and incorporated into the exhaust tubulation seal thereby effecting a discretely oriented electrical connection which is spatially isolated from the conventional array of connective pins.